B. 1. 1 (готовить) jam when my father came. 2. Their mother (мыть) plates when I came into the room. 3. The children (собирать) berries in the forest the whole day. 4. Mike (поливать) vegetable beds when Pete came to see him. 5. Nina (готовить) din- ner when Mike came into the room. 6. Mother (покупать) sweets for her children from 3 till 4 o'clock. 7. They (закончить) supper at 7 o'clock. 8. Masha (писать) a recipe at 6 o'clock. 9. We (чистить) potatoes from 2 till 3 o'clock. 10. We (стряпать) meat dumplings the whole evening.

Решение:

1. I cooked jam when my father came.
2. Their mother washed plates when I came into the room.
3. The children gathered berries in the forest the whole day.
4. Mike watered vegetable beds when Pete came to see him.
5. Nina cooked dinner when Mike came into the room.
6. Mother bought sweets for her children from 3 till 4 o'clock.
7. They finished supper at 7 o'clock.
8. Masha wrote a recipe at 6 o'clock.
9. We cleaned potatoes from 2 till 3 o'clock.
10. We cooked meat dumplings the whole evening.

Ответ: cooked; washed; gathered; watered; cooked; bought; finished; wrote; cleaned; cooked.